Sky & Telescope - March 2019 - 46

MARCH 2019 OBSERVING
Sun, Moon & Planets by Fred Schaaf
To find out what's
visible in the sky
from your location,
go to skypub.com/
almanac.

Three Worlds at Dawn
During the night's second half, three planets come into view.

fter the ﬁrst week of March,
Mercury disappears into the Sun's
afterglow. That yet again leaves dimming Mars as the only bright planet
visible in the evening sky - but at
least it beautifully drifts up near the
Pleiades by month's end. A few hours
after the late-evening setting of Mars,
Jupiter rises. It's followed about two
hours later by Saturn. Still later, Venus
rises, near dawn's ﬁrst light. By late
March, Mercury, having passed into
the morning sky, is creeping into view
below Venus around the time Jupiter is
highest in the south.

DUSK ONLY
Mercury was at greatest eastern elongation in the evening sky on February
27th. It starts March still setting about
1½ hours after the Sun and shining
at magnitude +0.1 with its 8″-wide
disk about 35% lit. But this innermost

planet is fading rapidly as its phase
thins and by about March 6th is fainter
than magnitude 2.0 and no longer readily detectable. Mercury reaches inferior
conjunction with the Sun on March
15th - just two inferior conjunctions
before the one in which it will transit across the face of the Sun for the
last time in 13 years (the transit this
November 11th will be visible in the
Americas, Europe, and Africa).
Neptune is at conjunction with the
Sun on March 7th and not viewable this
month. Uranus can still be observed
when the last of evening twilight fades,
though it appears lower and lower at
that time with each passing week in
March (see the September 2018 issue,
pages 48-49, for a ﬁnder chart).

DUSK AND EVENING
Mars is almost halfway up the southwest sky an hour after sunset this

month and doesn't set itself until
near midnight daylight-saving time.
Unfortunately, the Red Planet dims
even further in March - from magnitude 1.2 to 1.4 - with its disk decreasing from 5.3″ to 4.6″ wide. At least Mars
passes through a lovely section of the
zodiac in March, appearing some 3°
below the Pleiades at month's end.

PRE-DAWN AND DAWN
Jupiter rises around 2 a.m. standard
time on March 1st but not too long
after 1 a.m. daylight-saving time on
March 31st. Its magnitude brightens
from -2.0 to almost -2.3 this month, its
equatorial diameter increasing from 36″
to almost 40″. Jupiter passes through
western quadrature (90° west of the
Sun) in March, improving views of
some of the phenomena of its Galilean
satellites (see page 51). The best time
to get a sharp view of Jupiter's many

Dusk, March 1

Dawn, March 1-3

Dusk, March 11-13

45 minutes after sunset

45 minutes before sunrise

1 hour after sunset

PISCES

Moon
Mar 13

PEGASUS
Moon
Mar 1

Great Square

Saturn

β Cap

10°

Moon
Mar 2
Venus

Mercury
Moon
Mar 3

Aldebaran
Moon
Mar 12

Pleiades

TA U R U S
Moon
Mar 11
Mars

Looking West

M A RCH 2 019 * SK Y & TELESCOPE

Looking Southeast

Looking West-Southwest, halfway up

http://www.skypub.com/almanac http://www.skypub.com/almanac http://51

Sky & Telescope - March 2019

Table of Contents for the Digital Edition of Sky & Telescope - March 2019